The facility currently supports the research of numerous NIAMS IRP investigators. In addition, it is actively involved in training and assay support for all the IRP users who are unfamiliar with this technique. The Facility currently supports the NIAMS IRP community with the following instrumentation: (One) Beckman Coulter MoFlo cell sorter (3-laser excitation, 10-color detection, automated cell deposition unit) (One) BD Biosciences FACSAria IIIu high-speed sorter (5-laser excitation, 19-color detection, automated cell deposition unit) (One) Beckman Coulter CyAn analyzer (3-laser excitation, 9-color detection) (One) BD Biosciences FACSCanto II analyzer w/HTS (3-laser excitation, 8-color detection, high-throughput sampler) (Two) BD Biosciences FACSCalibur analyzers (2-laser excitation, 4-color detection) (One) Compucyte iCys Research Laser Scanning Cytometer (3-laser excitation, 5-parameter detection) And we expect to be installing four more cytometers by the end of September 2011. (One) BD Biosciences Influx cell sorter (7-laser excitation, 20-color detection, automated cell deposition unit, fully replaceable fluidics pack (to support the NCRM), spectral analyzer (One) BD Biosciences LSR Fortessa analyzer (7-laser excitation, 20-color detection, high-throughput sampler) (Two) BD Biosciences FACSVerse analyzers (3-laser excitation, 8-color detection, universal high-throughput sampler, volumetric measurement (for absolute cell counts) With the addition of the FACSVerse analyzers, the FACSCaliburs will be retired. More than one hundred fifty NIAMS flow cytometry users have been trained to date on the different platforms available in the facility. In 2011, we continue to use the revised, multi-level training scheme that was introduced in 2011. To provide a more logical training structure, a progressive group and individual-based training system is used to provide investigators and their staff better access to Flow Cytometry Section equipment and services. All new users attend a general introduction and orientation to facility equipment and policies. Then, according to needs and previous experience, they progress to individualized or group instruction on the instrument most appropriate for their particular research needs. After approval by the section leader, users can then operate the instruments unassisted. However, the FCS staff is always available for troubleshooting and consultation. In addition to the projects from those laboratories focused on mechanisms and dysfunctions of the immune system, the facility has continued to provide flow cytometry and sorting services to NIAMS laboratories engaged in disciplines not often served by flow cytometry: the Developmental Skin Biology Unit and the Laboratory of Muscle Stem Cells and Gene..The projects in these laboratories have been and continue to be quite encouraging. Usage of the facility has increased steadily over the last few years requiring the upgrade of our high-speed cell sorters and analyzers. This year, to deal with increasing demand, provide better tools for our investigators and support the newly-established National Center for Regenerative Medicine (NCRM), we are adding four new cytometers (listed above). Equipped with seven lasers and 20+ fluorescence detectors, both the Influx cell sorter and LSR Fortessa analyzer will provide state-of-the-art instrumentation that will allow NIAMS investigators to take advantage of the latest fluorochromes and fluorescent protein reporters. Those investigators whose research involves specimens that are not well suited to flow cytometry can continue to take advantage of the Sections laser scanning cytometer, the Compucyte iCys. This microscope-based instrument can provide fluorescent and morphological data on cells or tissue fixed to slides or multi-well plates. Along with typical immunophenotyping and co-localization studies, the iCys can also re-analyze specific cells over time for kinetics-based assays. While fulfilling his duties as the core Section Leader, Mr. James Simone, continues to be involved in the promotion of flow cytometry at NIH-wide level. As a member and co-chair of the Flow Cytometry Interest Group, he assists in organizing and promoting quarterly meetings that showcase leading researchers in the field and promote relationships with vendors of flow cytometry-related products. His long-time membership of the International Society for the Advancement of Cytometry (ISAC) and the ISAC Bio-Safety Committee helps facilitate the exchange of new ideas and information with peers from around the world.